How to Install UFW on Ubuntu (Step-by-Step)

This guide explains UFW in a practical, step-by-step way. It’s written for readers who want a safe, reversible setup (with verification and rollback steps).

Who is this for?

This article is for beginner-to-intermediate readers who prefer a step-by-step, reversible workflow. If you apply it on a production system, prepare backups and an access/rollback plan first.

What you’ll do in this post:

Understand what it is and when to use it

Check prerequisites and safety notes

Follow a step-by-step setup or configuration flow

Verify the result and troubleshoot common issues

Rollback / undo changes if needed

What is it, what does it do, who is it for?

UFW is commonly used on linux to improve reliability, security, or developer productivity. If you’re managing a VPS, deploying an app, or troubleshooting a system issue, the steps below provide a safe baseline you can adapt.

Prerequisites

A user with sudo privileges (or root access)

A recent Ubuntu/Debian-based system (adjust package manager for other distros)

A current backup / snapshot if this is a production server

An active SSH session + a fallback console access for risky network changes

Step-by-step (Terminal)

1) Update package index

sudo apt update

2) Install required packages (if applicable)

sudo apt install -y <package-name>

3) Apply a minimal safe configuration (example)

# Replace <...> with values for your setup

sudo <command> <args>

Verification

After applying changes, verify that the service/configuration is active and that you can still access the system.

sudo systemctl status <service>

# or

sudo <command> --version

Rollback / Undo

If something goes wrong, revert to the previous state using these typical options:

Remove the package or disable the service

Restore the previous configuration file from backup

Reload/restart the service and re-check logs

sudo systemctl disable --now <service>

sudo apt remove --purge -y <package-name>

Common issues and fixes

If you see errors, check logs and validate configs before restarting services:

sudo journalctl -u <service> -n 200 --no-pager

sudo <service> -t  # config test if supported

Official / trusted resources

Vendor / project official documentation

Operating system official docs (Ubuntu, Windows, etc.)

Security best-practices references (if applicable)

Tips and Best Practices

·         Split changes into small steps and verify after each step.

·         Before changing critical access (SSH/RDP), keep a secondary access method ready.

·         Document what you changed and why—it saves time during future maintenance.

·         Keep a simple update routine; behavior can differ across versions.

·         Reduce attack surface by disabling unnecessary features and closing unused ports.

·         Use logs and error messages as your primary signal instead of guessing.

Troubleshooting Notes

·         Permissions: admin rights, ownership, and file permissions.

·         Service state: systemctl status and logs (journalctl).

·         Networking: listening ports (ss/lsof), DNS, and firewall rules together.

·         Config: correct file path and a reload/restart after changes.

·         Rollback: restore from backup and re-apply changes carefully.